CuI p-type thin films for highly transparent thermoelectric p-n modules.

Area of Science:

• Materials Science
• Solid State Physics
• Nanotechnology

Background:

• Transparent thermoelectric (TE) materials are crucial for energy-efficient electronics, but p-type materials lag behind n-type counterparts.
• Existing transparent TE devices face limitations due to the scarcity of high-performance p-type materials.
• Copper iodide (CuI) presents potential for transparent p-type thermoelectric applications.

Purpose of the Study:

• To develop high-performance transparent p-type thermoelectric thin films of CuI.
• To investigate methods for maximizing optical transparency, electrical conductivity, and thermoelectric figure of merit (ZT).
• To fabricate and characterize the first planar fully transparent p-n type TE modules using the developed p-type CuI films.

Main Methods:

• Fabrication of p-type CuI thin films using three distinct deposition techniques.
• Characterization of optical transparency (>70% in visible range), electrical conductivity (σ = 1.1 × 10⁴ S m⁻¹), and thermoelectric properties (ZT = 0.22 at 300 K).
• Integration of CuI films with n-type gallium-doped zinc oxide (GZO) and indium tin oxide (ITO) electrodes to create planar p-n TE modules.

Main Results:

• Achieved significant improvements in optical and electrical properties of p-type CuI thin films.
• Demonstrated a thermoelectric figure of merit (ZT) of 0.22 at 300 K for the CuI films.
• Successfully fabricated and tested the first planar fully transparent p-n type TE modules, showing promising power output characteristics.

Conclusions:

• The developed transparent p-type CuI thin films overcome previous limitations in transparent thermoelectric materials.
• The fabricated transparent p-n TE modules open avenues for a new generation of transparent electronic applications.
• This work paves the way for widespread use of transparent thermoelectric devices in various technological fields.